Billet rocker box unit



FIG. 1 is a front left perspective view of a billet rocker box unit showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a left view thereof; and,

FIG. 7 is a right view of the billet rocker box unit. 

The ornamental design for a billet rocker box unit, as shown and described. 